ZOOLOGICAL NOTES 49 



ZOOLOGICAL NOTES. 



The Black Rat in Orkney. The known information about the 

 Black Rat (Mas. rattns, Linnasus, referred to more definitely by 

 Millais in the "Zoologist," June 1905, as Mns rattns rattns} in Orkney, 

 previous to 1848, is summarised by Baikie and Heddle in three lines 

 "The Black Rat, which was said formerly to have been numerous 

 throughout Orkney, is now confined to a single island, viz. South 

 Ronaldshay, and even there is quickly decreasing." Harvie-Brown 

 and Buckley, in 1891, write that it is still stated to occur on the 

 same island, but that they have not had an opportunity of verifying 

 the statement. In the " Annals ;I 1900, p. 18 i, Mr. J. M. B. Taylor 

 mentions a South Ronaldshay specimen just added to the Paisley 

 Museum. We are able to say that this specimen and another 

 which was too far gone for preservation were sent from the farm of 

 Burwick. In August 1905 Mr. H. Drummond Simpson and I, 

 during a visit to South Ronaldshay, made careful enquiries about 

 this animal locally known as the Blue Rat and we ascertained 

 that it still holds its own on the island. We heard of its occurrence 

 at St. Margaret's Hope, and at the farms of Brough and Burwick in 

 the south of the island. Mr. Budge, Brough, told us that one was 

 seen near his farm at the time of our visit, and Mr. Allan, Burwick, 

 informed us that the Blue Rat was at one time a pest on his farm, 

 but was driven off by the introduction of concrete flooring. Our 

 informants agreed that in summer this species lives mainly by the 

 shore. Mr. Allan took us to a cave at Burwick Castle, an old 

 Brough, where he had once found a nest of young Blue Rats, and 

 we left a rat-trap there for a night, but unavailingly. Our efforts to 

 secure a specimen failed, but we left a rat-trap with Mr. Allan, who 

 kindly agreed to capture specimens for us on their return to his 

 farm in winter. A pair came to the farm at the beginning of 

 November; the male was trapped on i3th November, and the 

 female on igth November. The measurements of the male, taken 

 by Mr. Eagle Clarke and myself, were: head and body 179 mm., 

 tail 204 mm., hind foot without claws 34.5 mm., ear 24 mm. The 

 weight was 149.5 grammes. The corresponding measurements of 

 the female, taken by myself, were: head and body 156 mm., tail 

 196 mm., hind foot 35 mm., ear 23 mm. It may be worth while 

 putting these occurrences on record, in view of the opening of a 

 pier at St. Margaret's Hope in the near future. We also ascertained 

 that the Blue Rat occurs on the Calf of Flotta, our informant stating 

 that he had seen two held prisoners by their feet by limpets which 

 they had probably been endeavouring to get at to devour. ROBERT 

 (iODFREY, Edinburgh. 



The Food of the Bank Vole. It is not often that one has an 

 opportunity of ascertaining what constitutes the food of some of our 



57 K 



